workbox-build/src/lib/get-composite-details.ts

A module that integrates into your build process, helping you generate a manifest of local files that workbox-sw should precache.

/*
  Copyright 2018 Google LLC

  Use of this source code is governed by an MIT-style
  license that can be found in the LICENSE file or at
  https://opensource.org/licenses/MIT.
*/

import crypto from 'crypto';

import {FileDetails} from '../types';

export function getCompositeDetails(
  compositeURL: string,
  dependencyDetails: Array<FileDetails>,
): FileDetails {
  let totalSize = 0;
  let compositeHash = '';

  for (const fileDetails of dependencyDetails) {
    totalSize += fileDetails.size;
    compositeHash += fileDetails.hash;
  }

  const md5 = crypto.createHash('md5');
  md5.update(compositeHash);
  const hashOfHashes = md5.digest('hex');

  return {
    file: compositeURL,
    hash: hashOfHashes,
    size: totalSize,
  };
}